Magnetoresistors are resistors whose resistance is varied by applying a magnetic field across the resistor. Magnetoresistors can be used, in conjunction with a permanent magnet, to sense the distance between the magnet and the magnetoresistors. This leads to their potential application in position sensing devices, such as used in the automotive industry. There are essentially two classes of magnetoresistors. One class of these devices, known as magnetodiodes, operates on the bases of selective reCOmbination of electrons and holes. The other class operates on the deflection of the current paths in a rectangular or circular resistor. The performance of the first class of devices depends strongly on the electron-hole recombination rate, and the performance of the second class of devices depends on the carrier mobilities. Both the electron-hole recombination rate and the carrier mobilities are temperature dependent quantities. Thus, to date, most field sensors using these magnetoresistors have large temperature coefficients. In the automotive industry, where there are wide variations in the temperature to which these sensors are subjected, it would be desirable to have a magnetoresistor which not only has a large variation in resistance, but also has a low temperature coefficient.